In general, when booking your flight to Bucharest, January is the cheapest month on average.
In general, most flyers find the cheapest time to book a flight to Bucharest is about 60 days prior.
From most locations, the cheapest flights to Bucharest are found on a Thursday. Booking a Sunday departure is usually the most expensive.
On average you can find the best deals on plane tickets to Bucharest when looking for flights with evening departure times.